<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>盒子模型</title>
  <style>
    .box{
      width: 200px;
      height: 80px;
      background: pink;
      border: 8px solid blue;
      padding: 15px;
      margin: 20;
    }
  </style>
</head>
<body>
<p class="box">
  这是一个盒子
</p>
</body>
</html>